[go: up one dir, main page]

WO2013033361A1 - Systèmes et procédés pour optimiser des débits de transmission de données sans fil - Google Patents

Systèmes et procédés pour optimiser des débits de transmission de données sans fil Download PDF

Info

Publication number
WO2013033361A1
WO2013033361A1 PCT/US2012/053088 US2012053088W WO2013033361A1 WO 2013033361 A1 WO2013033361 A1 WO 2013033361A1 US 2012053088 W US2012053088 W US 2012053088W WO 2013033361 A1 WO2013033361 A1 WO 2013033361A1
Authority
WO
WIPO (PCT)
Prior art keywords
modulation
coding scheme
access point
feedback response
request
Prior art date
Application number
PCT/US2012/053088
Other languages
English (en)
Inventor
Santosh Paul Abraham
Simone Merlin
Hemanth Sampath
Zhi Quan
Rahul DANGUI
Original Assignee
Qualcomm Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Qualcomm Incorporated filed Critical Qualcomm Incorporated
Publication of WO2013033361A1 publication Critical patent/WO2013033361A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/02—Arrangements for optimising operational condition
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0002—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the transmission rate
    • H04L1/0003—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the transmission rate by switching between different modulation schemes
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0009—Systems modifying transmission characteristics according to link quality, e.g. power backoff by adapting the channel coding
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0015—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the adaptation strategy
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
    • H04L1/0026—Transmission of channel quality indication
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00—Arrangements for detecting or preventing errors in the information received
    • H04L1/0001—Systems modifying transmission characteristics according to link quality, e.g. power backoff
    • H04L1/0023—Systems modifying transmission characteristics according to link quality, e.g. power backoff characterised by the signalling
    • H04L1/0028—Formatting
    • H04L1/0029—Reduction of the amount of signalling, e.g. retention of useful signalling or differential signalling

Definitions

  • the present application relates generally to wireless communications, and more specifically to systems, methods, and devices for optimizing wireless transmission data rates. Certain aspects herein relate to determining the fastest available data rate for communication between two wireless nodes.
  • communications networks are used to exchange messages among several interacting spatially-separated devices.
  • Networks may be classified according to geographic scope, which could be, for example, a metropolitan area, a local area, or a personal area. Such networks would be designated respectively as a wide area network (WAN), metropolitan area network (MAN), local area network (LAN), or personal area network (PAN).
  • WAN wide area network
  • MAN metropolitan area network
  • LAN local area network
  • PAN personal area network
  • Networks also differ according to the switching/routing technique used to interconnect the various network nodes and devices (e.g. circuit switching vs. packet switching), the type of physical media employed for transmission (e.g. wired vs. wireless), and the set of communication protocols used (e.g. Internet protocol suite, SONET (Synchronous Optical Networking), Ethernet, etc.).
  • SONET Synchronous Optical Networking
  • Wireless networks are often preferred when the network elements are mobile and thus have dynamic connectivity needs, or if the network architecture is formed in an ad hoc, rather than fixed, topology.
  • Wireless networks employ intangible physical media in an unguided propagation mode using electromagnetic waves in the radio, microwave, infra-red, optical, etc. frequency bands. Wireless networks advantageously facilitate user mobility and rapid field deployment when compared to fixed wired networks.
  • the devices in a wireless network may transmit/receive information between each other.
  • the information may comprise packets, which in some aspects may be referred to as data units.
  • the packets may include overhead information (e.g., header information, packet properties, etc.) that helps in routing the packet through the network, identifying the data in the packet, processing the packet, etc., as well as data, for example user data, multimedia content, etc. as might be carried in a payload of the packet.
  • overhead information e.g., header information, packet properties, etc.
  • the selection of a modulation and coding scheme is associated with the data rate for communicating between devices.
  • devices are unaware of the optimal modulation and coding scheme because, for example, the devices have not communicated recently and therefore are unaware of the state of devices in a wireless network and the state of the medium.
  • devices will either use a modulation and coding scheme associated with a low data rate or must expend significant resources using convergence algorithms to eventually determine the optimal modulation and coding scheme.
  • convergence algorithms will often not have enough time to determine the optimal modulation and coding scheme before transmission of the packets completes.
  • One aspect of the disclosure provides a method for wireless communication.
  • the method includes sending a modulation and coding scheme request to an access point.
  • the modulation and coding scheme request is sent using a first physical layer preamble frame.
  • the method further includes receiving at a station a modulation and coding scheme feedback response from the access point in response to sending the modulation and coding scheme request.
  • the modulation and coding scheme feedback response is received as a second physical layer preamble frame.
  • the method includes determining a modulation and coding scheme based on the modulation and coding scheme feedback response.
  • the method includes transmitting data to the access point using the identified modulation and coding scheme.
  • the method includes identifying the modulation and coding scheme based on a modulation and coding scheme field associated with the second physical layer preamble frame. Further, the method may include identifying the modulation and coding scheme based on the modulation and coding scheme field including a bit pattern not associated with a valid modulation and coding scheme.
  • the modulation and coding scheme feedback response specifies the modulation and coding scheme associated with the fastest data rate that the station can use to ensure correct decoding of data transmitted to the access point. In some instances, the modulation and coding scheme feedback response specifies the modulation and coding scheme associated with the fastest data rate that the station can use to ensure correct decoding of data transmitted to the access point at a specific time.
  • the method can include identifying to the access point a set of modulation and coding schemes supported by the station.
  • the modulation and coding scheme is associated with the set of modulation and coding schemes.
  • the modulation and coding scheme feedback response can specify the modulation and coding scheme associated with the fastest data rate from the set of modulation and coding schemes that the station can use to ensure correct decoding of data transmitted to the access point.
  • the modulation and coding scheme feedback response may specify a number of available streams. Further, the method may include sending the modulation and coding scheme request using a default modulation and coding scheme. In addition, the modulation and coding scheme feedback response may be transmitted a short interframe space after the modulation and coding scheme feedback request is transmitted. In some embodiments, the method includes receiving an acknowledgement packet in response to transmitting the data.
  • a length field associated with the modulation and coding scheme request is set to zero. Further, a length field associated with the modulation and coding scheme feedback response may be set to zero. In some cases, a length field associated with the modulation and coding scheme feedback response may be set to a value less than the smallest valid 802.1 1 frame size associated with at least one of the following: a control frame, a data frame, and a management frame.
  • the modulation and coding scheme request includes an identifier associated with the access point. This identifier can include at least one of the following: a hash of a SSID, a hash of a BSSID, and a MAC address.
  • Another aspect of the disclosure provides a method for wireless communication.
  • the method includes receiving at an access point a modulation and coding scheme request from a station, wherein the modulation and coding scheme request is received as a first physical layer preamble frame. Further, the method includes sending to the station a modulation and coding scheme feedback response in response to receiving the modulation and coding scheme request.
  • the modulation and coding scheme field associated with the modulation and coding scheme feedback response can specify a modulation and coding scheme. Further, the modulation and coding scheme feedback response maybe sent using a second physical layer preamble frame.
  • the method may further include receiving data from the station using the modulation and coding scheme.
  • the wireless communication apparatus includes a transmitter configured to transmit a modulation and coding scheme request to an access point.
  • the modulation and coding scheme request may be sent using a first physical layer preamble frame.
  • the wireless communication apparatus includes a receiver configured to receive a modulation and coding scheme feedback response from the access point in response to transmission of the modulation and coding scheme request.
  • the modulation and coding scheme feedback response may be received as a second physical layer preamble frame.
  • the wireless communication apparatus includes a processor configured to determine a modulation and coding scheme based on the modulation and coding scheme feedback response.
  • the transmitter may be further configured to transmit data to the access point using the identified modulation and coding scheme.
  • the access point includes at least one antenna. Further, the access point includes a receiver configured to receive via the at least one antenna a modulation and coding scheme request from a station. The modulation and coding scheme request may be received as a first physical layer preamble frame. The access point also includes a transmitter configured to send via the at least one antenna to the station a modulation and coding scheme feedback response in response to receipt of the modulation and coding scheme request. A modulation and coding scheme field associated with the modulation and coding scheme feedback response specifies a modulation and coding scheme. Further, the modulation and coding scheme feedback response may be sent using a second physical layer preamble frame. In addition, the receive may be further configured to receive data from the station using the modulation and coding scheme.
  • the apparatus includes means for sending a modulation and coding scheme request to an access point.
  • the modulation and coding scheme request may be sent using a first physical layer preamble frame.
  • the apparatus includes means for receiving a modulation and coding scheme feedback response from the access point.
  • the modulation and coding scheme feedback response may be received as a second physical layer preamble frame.
  • the apparatus includes means for determining a modulation and coding scheme based on the modulation and coding scheme feedback response.
  • the apparatus includes means for transmitting data to the access point using the identified modulation and coding scheme.
  • Another embodiment of the disclosure provides for an access point for wireless communication.
  • the access point includes means for receiving a modulation and coding scheme request from a station.
  • the modulation and coding scheme request may be received as a first physical layer preamble frame.
  • the access point includes means for sending to the station a modulation and coding scheme feedback response.
  • a modulation and coding scheme field associated with the modulation and coding scheme feedback response specifies a modulation and coding scheme.
  • the modulation and coding scheme feedback response may be sent using a second physical layer preamble frame.
  • the access point includes means for receiving data from the station using the modulation and coding scheme.
  • a non-transitory physical computer storage comprising computer executable instructions configured to implement a method for wireless communication.
  • the method includes sending a modulation and coding scheme request to an access point.
  • the modulation and coding scheme request is sent using a first physical layer preamble frame.
  • the method further includes receiving at a station a modulation and coding scheme feedback response from the access point in response to sending the modulation and coding scheme request.
  • the modulation and coding scheme feedback response is received as a second physical layer preamble frame.
  • the method includes determining a modulation and coding scheme based on the modulation and coding scheme feedback response.
  • the method includes transmitting data to the access point using the identified modulation and coding scheme.
  • Another embodiment of the disclosure provides for a non-transitory physical computer storage comprising computer executable instructions configured to implement a method for wireless communication.
  • the method includes The method includes receiving at an access point a modulation and coding scheme request from a station, wherein the modulation and coding scheme request is received as a first physical layer preamble frame. Further, the method includes sending to the station a modulation and coding scheme feedback response in response to receiving the modulation and coding scheme request.
  • the modulation and coding scheme field associated with the modulation and coding scheme feedback response can specify a modulation and coding scheme. Further, the modulation and coding scheme feedback response maybe sent using a second physical layer preamble frame.
  • the method may further include receiving data from the station using the modulation and coding scheme.
  • FIG. 1 illustrates an example of a wireless communication system in which aspects of the present disclosure may be employed.
  • FIG. 2 illustrates an example of a wireless device that may be employed within the wireless communication system of FIG. 1 .
  • FIG. 3 illustrates an example of components that may be included within the wireless device of FIG. 2 to transmit wireless communications.
  • FIG. 4 illustrates an example of components that may be included within the wireless device of FIG. 2 to transmit wireless communications.
  • FIG. 5 illustrates an example of a physical layer data unit.
  • FIG. 6 presents a flowchart for one embodiment of a data transmission process.
  • FIG. 7 presents a flowchart for one embodiment of a data reception process.
  • FIG. 8 illustrates an example of a packet flow in accordance with an embodiment of the present disclosure.
  • FIG. 9 illustrates another example of a wireless device that may be employed within the wireless communication system of FIG. 1 .
  • FIG. 10 illustrates an example of an access point that may be employed within the wireless communication system of FIG. 1 .
  • Wireless network technologies may include various types of wireless local area networks (WLANs).
  • WLAN may be used to interconnect nearby devices together, employing widely used networking protocols.
  • the various aspects described herein may apply to any communication standard, such as WiFi or, more generally, any member of the IEEE 802.1 1 family of wireless protocols.
  • the various aspects described herein may be used as part of the IEEE 802.1 1 ah protocol, which uses sub-1 GHz bands.
  • wireless signals in a sub-gigahertz band may be transmitted according to the 802.1 1 ah protocol using orthogonal frequency- division multiplexing (OFDM), direct-sequence spread spectrum (DSSS) communications, a combination of OFDM and DSSS communications, or other schemes.
  • OFDM orthogonal frequency- division multiplexing
  • DSSS direct-sequence spread spectrum
  • Implementations of the 802.1 1 ah protocol may be used for sensors, metering, and smart grid networks.
  • aspects of certain devices implementing the 802.1 1 ah protocol may consume less power than devices implementing other wireless protocols, and/or may be used to transmit wireless signals across a relatively long range, for example about one kilometer or longer.
  • a WLAN includes various devices which are the components that access the wireless network.
  • access points access points
  • STAs stations
  • an AP serves as a hub or base station for the WLAN and a STA serves as a user of the WLAN.
  • an STA may be a laptop computer, a personal digital assistant (PDA), a mobile phone, etc.
  • PDA personal digital assistant
  • an STA connects to an AP via a WiFi (e.g., IEEE 802.1 1 protocol such as 802.1 1 ah) compliant wireless link to obtain general connectivity to the Internet or to other wide area networks.
  • WiFi e.g., IEEE 802.1 1 protocol such as 802.1 1 ah
  • an STA may also be used as an AP.
  • An access point may also comprise, be implemented as, or known as a NodeB, Radio Network Controller (“RNC”), eNodeB, Base Station Controller (“BSC”), Base Transceiver Station (“BTS”), Base Station (“BS”), Transceiver Function (“TF”), Radio Router, Radio Transceiver, or some other terminology.
  • RNC Radio Network Controller
  • BSC Base Station Controller
  • BTS Base Transceiver Station
  • BS Base Station
  • Transceiver Function TF
  • Radio Router Radio Transceiver
  • a station “STA” may also comprise, be implemented as, or known as an access terminal ("AT”), a subscriber station, a subscriber unit, a mobile station, a remote station, a remote terminal, a user terminal, a user agent, a user device, user equipment, or some other terminology.
  • an access terminal may comprise a cellular telephone, a cordless telephone, a Session Initiation Protocol ("SIP”) phone, a wireless local loop (“WLL”) station, a personal digital assistant (“PDA”), a handheld device having wireless connection capability, or some other suitable processing device connected to a wireless modem.
  • SIP Session Initiation Protocol
  • WLL wireless local loop
  • PDA personal digital assistant
  • a phone e.g., a cellular phone or smartphone
  • a computer e.g., a laptop
  • a portable communication device e.g., a headset
  • a portable computing device e.g., a personal data assistant
  • an entertainment device e.g., a music or video device, or a satellite radio
  • gaming device or system e.g., a gaming console, a global positioning system device, or any other suitable device that is configured to communicate via a wireless medium.
  • certain of the devices described herein may implement the 802.1 1 ah standard, for example.
  • Such devices whether used as an STA or AP or other device, may be used for smart metering or in a smart grid network.
  • Such devices may provide sensor applications or be used in home automation.
  • the devices may instead or in addition be used in a healthcare context, for example for personal healthcare. They may also be used for surveillance, to enable extended-range Internet connectivity (e.g. for use with hotspots), or to implement machine-to-machine communications.
  • FIG. 1 illustrates an example of a wireless communication system 100 in which aspects of the present disclosure may be employed.
  • the wireless communication system 100 may operate pursuant to a wireless standard, for example the 802.1 1 ah standard.
  • the wireless communication system 100 may include an AP 104, which communicates with STAs 106.
  • a variety of processes and methods may be used for transmissions in the wireless communication system 100 between the AP 104 and the STAs 106.
  • signals may be sent and received between the AP 104 and the STAs 106 in accordance with OFDM/OFDMA techniques. If this is the case, the wireless communication system 100 may be referred to as an OFDM/OFDMA system.
  • signals may be sent and received between the AP 104 and the STAs 106 in accordance with CDMA techniques. If this is the case, the wireless communication system 100 may be referred to as a CDMA system.
  • a communication link that facilitates transmission from the AP 104 to one or more of the STAs 106 may be referred to as a downlink (DL) 108, and a communication link that facilitates transmission from one or more of the STAs 106 to the AP 104 may be referred to as an uplink (UL) 1 10.
  • DL downlink
  • UL uplink
  • a downlink 108 may be referred to as a forward link or a forward channel
  • an uplink 1 10 may be referred to as a reverse link or a reverse channel.
  • the AP 104 may act as a base station and provide wireless communication coverage in a basic service area (BSA) 102.
  • BSA basic service area
  • the AP 104 along with the STAs 106 associated with the AP 104 that use the AP 104 for communication may be referred to as a basic service set (BSS).
  • BSS basic service set
  • the wireless communication system 100 may not have a central AP 104, but rather may function as a peer-to-peer network between the STAs 106. Accordingly, the functions of the AP 104 described herein may alternatively be performed by one or more of the STAs 106.
  • the STAs 106 are not limited in type and may include a variety of different STAs.
  • STAs 106 can include a cellular phone 106a, a television 106b, a laptop 106c, and a sensor 106d (e.g. a weather sensor or other sensor capable of communicating using a wireless protocol), to name a few.
  • a sensor 106d e.g. a weather sensor or other sensor capable of communicating using a wireless protocol
  • FIG. 2 illustrates various components that may be utilized in a wireless device 202 that may be employed within the wireless communication system 100.
  • the wireless device 202 is an example of a device that may be configured to implement the various methods described herein.
  • the wireless device 202 may comprise the AP 104 or one of the STAs 106.
  • the wireless device 202 may include a processor 204 which controls operation of the wireless device 202.
  • the processor 204 may also be referred to as a central processing unit (CPU).
  • Memory 206 which may include both read-only memory (ROM) and random access memory (RAM), provides instructions and data to the processor 204.
  • a portion of the memory 206 may also include non-volatile random access memory (NVRAM).
  • the processor 204 typically performs logical and arithmetic operations based on program instructions stored within the memory 206.
  • the instructions in the memory 206 may be executable to implement the methods described herein.
  • the processor 204 may comprise or be a component of a processing system implemented with one or more processors.
  • the one or more processors may be implemented with any combination of general-purpose microprocessors, microcontrollers, digital signal processors (DSPs), field programmable gate array (FPGAs), programmable logic devices (PLDs), controllers, state machines, gated logic, discrete hardware components, dedicated hardware finite state machines, or any other suitable entities that can perform calculations or other manipulations of information.
  • the processing system may also include machine-readable media for storing software.
  • Software shall be construed broadly to mean any type of instructions, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Instructions may include code (e.g., in source code format, binary code format, executable code format, or any other suitable format of code). The instructions, when executed by the one or more processors, cause the processing system to perform the various functions described herein.
  • the wireless device 202 may also include a transmitter 210 and a receiver 212 to allow transmission and reception of data between the wireless device 202 and a remote location. Further, the transmitters 210 and the receiver 212 may be configured to allow transmission and reception of setup and/or configuration packets or frames between the wireless device 202 and a remote location including, for example, an AP.
  • the transmitter 210 and receiver 212 may be combined into a transceiver 214.
  • An antenna 216 may be attached to the housing 208 and electrically coupled to the transceiver 214. Alternatively, or additionally, the wireless device 202 may include an antenna 216 formed as part of the housing 208 or may be an internal antenna.
  • the wireless device 202 may also include (not shown) multiple transmitters, multiple receivers, multiple transceivers, and/or multiple antennas.
  • the wireless device 202 may also include a signal detector 218 that may be used in an effort to detect and quantify the level of signals received by the transceiver 214.
  • the signal detector 218 may detect such signals as total energy, energy per subcarrier per symbol, power spectral density and other signals.
  • the wireless device 202 may also include a digital signal processor (DSP) 220 for use in processing signals.
  • DSP 220 may be configured to generate a data unit for transmission.
  • the data unit may comprise a physical layer data unit (PPDU).
  • PPDU physical layer data unit
  • the PPDU is referred to as a packet or a frame.
  • the wireless device 202 may further comprise a user interface 222 in some aspects.
  • the user interface 222 may comprise a keypad, a microphone, a speaker, and/or a display.
  • the user interface 222 may include any element or component that conveys information to a user of the wireless device 202 and/or receives input from the user.
  • the various components of the wireless device 202 may be housed within a housing 208. Further, the various components of the wireless device 202 may be coupled together by a bus system 226.
  • the bus system 226 may include a data bus, for example, as well as a power bus, a control signal bus, and a status signal bus in addition to the data bus.
  • a data bus for example, as well as a power bus, a control signal bus, and a status signal bus in addition to the data bus.
  • Those of skill in the art will appreciate the components of the wireless device 202 may be coupled together, or may accept or provide inputs to each other using some other mechanism.
  • processor 204 may be used to implement not only the functionality described above with respect to the processor 204, but also to implement the functionality described above with respect to the signal detector 218 and/or the DSP 220. Further, each of the components illustrated in FIG. 2 may be implemented using a plurality of separate elements.
  • the wireless device 202 may comprise an AP 104 or a STA 106, and may be used to transmit and/or receive communications.
  • FIG. 3 illustrates various components that may be utilized in the wireless device 202 to transmit wireless communications.
  • the components illustrated in FIG. 3 may be used, for example, to transmit OFDM communications.
  • the components illustrated in FIG. 3 are used to transmit data units with training fields with peak-to-power average ratio is as low as possible, as will be discussed in additional detail below.
  • the wireless device 202 configured with the components illustrated in FIG. 3 is hereinafter referred to as a wireless device 202a.
  • the wireless device 202a may comprise a modulator 302 configured to modulate bits for transmission.
  • the modulator 302 may determine a plurality of symbols from bits received from the processor 204 or the user interface 222, for example by mapping bits to a plurality of symbols according to a constellation.
  • the bits may correspond to user data or to control information.
  • the bits are received in codewords.
  • the modulator 302 comprises a QAM (quadrature amplitude modulation) modulator, for example a 16-QAM modulator or a 64-QAM modulator.
  • the modulator 302 comprises a binary phase-shift keying (BPSK) modulator or a quadrature phase-shift keying (QPSK) modulator.
  • BPSK binary phase-shift keying
  • QPSK quadrature phase-shift keying
  • the wireless device 202a may further comprise a transform module 304 configured to convert symbols or otherwise modulated bits from the modulator 302 into a time domain.
  • the transform module 304 is illustrated as being implemented by an inverse fast Fourier transform (IFFT) module.
  • IFFT inverse fast Fourier transform
  • the modulator 302 and the transform module 304 are illustrated as being implemented in the DSP 220. In some aspects, however, one or both of the modulator 302 and the transform module 304 are implemented in the processor 204 or in another element of the wireless device 202.
  • the DSP 220 may be configured to generate a data unit for transmission.
  • the modulator 302 and the transform module 304 may be configured to generate a data unit comprising a plurality of fields including control information and a plurality of data symbols.
  • the fields including the control information may comprise one or more training fields, for example, and one or more signal (SIG) fields.
  • Each of the training fields may include a known sequence of bits or symbols.
  • Each of the SIG fields may include information about the data unit, for example a description of a length or data rate of the data unit.
  • the wireless device 202a may further comprise a digital to analog converter 306 configured to convert the output of the transform module into an analog signal.
  • a digital to analog converter 306 configured to convert the output of the transform module into an analog signal.
  • the time- domain output of the transform module 306 may be converted to a baseband OFDM signal by the digital to analog converter 306.
  • the digital to analog converter 306 may be implemented in the processor 204 or in another element of the wireless device 202. In some aspects, the digital to analog converter 306 is implemented in the transceiver 214 or in a data transmission processor.
  • the analog signal may be wirelessly transmitted by the transmitter 210.
  • the analog signal may be further processed before being transmitted by the transmitter 210, for example by being filtered or by being upconverted to an intermediate or carrier frequency.
  • the transmitter 210 includes a transmit amplifier 308.
  • the analog signal Prior to being transmitted, the analog signal may be amplified by the transmit amplifier 308.
  • the amplifier 308 comprises a low noise amplifier (LNA).
  • the transmitter 210 is configured to transmit one or more packets, frames, or data units in a wireless signal based on the analog signal.
  • the data units may be generated using the processor 204 and/or the DSP 220, for example using the modulator 302 and the transform module 304 as discussed above. Data units that may be generated and transmitted as discussed above are described in additional detail below with respect to FIGs. 5-8.
  • FIG. 4 illustrates various components that may be utilized in the wireless device 202 to receive wireless communications.
  • the components illustrated in FIG. 4 may be used, for example, to receive OFDM communications.
  • the components illustrated in FIG. 4 are used to receive packets, frames, or data units that include one or more training fields, as will be discussed in additional detail below.
  • the components illustrated in FIG. 4 may be used to receive data units transmitted by the components discussed above with respect to FIG. 3.
  • the wireless device 202 configured with the components illustrated in FIG. 4 is hereinafter referred to as a wireless device 202b.
  • the receiver 212 is configured to receive one or more packets, frames, or data units in a wireless signal. Data units that may be received, decoded, or otherwise processed as discussed below are described in additional detail with respect to FIGs. 5-8.
  • the receiver 212 includes a receive amplifier 401 .
  • the receive amplifier 401 may be configured to amplify the wireless signal received by the receiver 212.
  • the receiver 212 is configured to adjust the gain of the receive amplifier 401 using an automatic gain control (AGC) procedure.
  • AGC automatic gain control
  • the automatic gain control uses information in one or more received training fields, such as a received short training field (STF) for example, to adjust the gain.
  • STF received short training field
  • the amplifier 401 comprises an LNA.
  • the wireless device 202b may comprise an analog to digital converter
  • the wireless signal may be processed before being converted by the digital to analog converter 402, for example by being filtered or by being downconverted to an intermediate or baseband frequency.
  • the analog to digital converter 402 may be implemented in the processor 204 or in another element of the wireless device 202. In some aspects, the analog to digital converter 402 is implemented in the transceiver 214 or in a data receive processor.
  • the wireless device 202b may further comprise a transform module 404 configured to convert the representation the wireless signal into a frequency spectrum.
  • the transform module 404 is illustrated as being implemented by a fast Fourier transform (FFT) module.
  • FFT fast Fourier transform
  • the transform module may identify a symbol for each point that it uses.
  • the wireless device 202b may further comprise a channel estimator and equalizer 405 configured to form an estimate of the channel over which the data unit is received, and to remove certain effects of the channel based on the channel estimate.
  • the channel estimator may be configured to approximate a function of the channel
  • the channel equalizer may be configured to apply an inverse of that function to the data in the frequency spectrum.
  • the channel estimator and equalizer 405 uses information in one or more received training fields, such as a long training field (LTF) for example, to estimate the channel.
  • the channel estimate may be formed based on one or more LTFs received at the beginning of the data unit. This channel estimate may thereafter be used to equalize data symbols that follow the one or more LTFs.
  • one or more additional LTFs may be received in the data unit.
  • the channel estimate may be updated or a new estimate formed using the additional LTFs. This new or update channel estimate may be used to equalize data symbols that follow the additional LTFs.
  • the new or updated channel estimate is used to re-equalize data symbols preceding the additional LTFs.
  • the wireless device 202b may further comprise a demodulator 406 configured to demodulate the equalized data.
  • the demodulator 406 may determine a plurality of bits from symbols output by the transform module 404 and the channel estimator and equalizer 405, for example by reversing a mapping of bits to a symbol in a constellation.
  • the bits may be processed or evaluated by the processor 204, or used to display or otherwise output information to the user interface 222. In this way, data and/or information may be decoded.
  • the bits correspond to codewords.
  • the demodulator 406 comprises a QAM (quadrature amplitude modulation) demodulator, for example a 16-QAM demodulator or a 64-QAM demodulator.
  • the demodulator 406 comprises a binary phase-shift keying (BPSK) demodulator or a quadrature phase-shift keying (QPSK) demodulator.
  • BPSK binary phase-shift keying
  • QPSK quadrature phase-shift keying
  • the transform module 404 the channel estimator and equalizer
  • the demodulator 406 are illustrated as being implemented in the DSP 220. In some aspects, however, one or more of the transform module 404, the channel estimator and equalizer 405, and the demodulator 406 are implemented in the processor 204 or in another element of the wireless device 202.
  • the wireless signal received at the receiver 212 comprises one or more data units.
  • the data units or data symbols therein may be decoded evaluated or otherwise evaluated or processed.
  • the processor 204 and/or the DSP 220 may be used to decode data symbols in the data units using the transform module 404, the channel estimator and equalizer 405, and the demodulator 406.
  • Data units exchanged by the AP 104 and the STA 106 may include control information or data, as discussed above.
  • these data units may be referred to as physical layer protocol data units (PPDUs).
  • PPDUs physical layer protocol data units
  • a PPDU may be referred to as a packet, frame, or physical layer packet.
  • Each PPDU may comprise a preamble and a payload.
  • the preamble may include training fields and a SIG field.
  • the payload may comprise a Media Access Control (MAC) header or data for other layers, and/or user data, for example.
  • the payload may be transmitted using one or more data symbols.
  • the systems, methods, and devices herein may utilize data units with training fields whose peak-to-power ratio has been minimized.
  • FIG. 5 illustrates an example of a frame 500.
  • the frame 500 may comprise a PPDU for use with the wireless device 202.
  • the frame 500 may be used by legacy devices or devices implementing a legacy standard or downclocked version thereof.
  • the frame 500 includes a preamble 510.
  • the preamble 510 may comprise a variable number of repeating STF 512 symbols, one or more LTF 514 symbols, and a SIGNAL or SIG field 520 In one implementation 10 repeated STF 512 symbols may be set followed by two LTF 512 symbols.
  • the STF 512 may be used by the receiver 212 to perform automatic gain control to adjust the gain of the receive amplifier 401 , as discussed above. Furthermore, the STF 512 sequence may be used by the receiver 212 for packet detection, rough timing, and other settings.
  • the LTF 514 may be used by the channel estimator and equalizer 405 to form an estimate of the channel over which the frame 500 is received.
  • the SIG field 520 may be one OFDM signal that includes various information relating to the transmission rate, the length of the frame 500, and the like.
  • the frame 500 may additionally include a variable number of data symbols 530, such as OFDM data symbols.
  • the frame 500 includes the preamble 510 without including data symbols 530.
  • the frame 500 can be used to determine a modulation and coding scheme (MCS) more efficiently compared to using a frame with data symbols 530.
  • MCS modulation and coding scheme
  • the size of the frame 500 including the training symbols 514 may be computed based on the SIG field 520, and the STF 512 may be used by the receiver 212 to adjust the gain of the receive amplifier 401 . Further, a LTF 514 may be used by the channel estimator and equalizer 405 to form an estimate of the channel over which the frame 500 is received. The channel estimate may be used by the processor 220 to decode the plurality of data symbols 530 that follow the preamble 510.
  • the frame 500 illustrated in FIG. 5 is only an example of a frame or packet that may be used in the system 100 and/or with the wireless device 202. Those having ordinary skill in the art will appreciate that a greater or fewer number of the STFs 412 or LTFs 514 and/or the data symbols 530 may be included in the frame 500. In addition, one or more symbols or fields may be included in the frame 500 that are not illustrated in FIG. 5, and one or more of the illustrated fields or symbols may be omitted.
  • the SIG field 520 may include a varying number and type of different fields. According to several embodiments, the SIG field 520 may include fields that facilitate identifying information associated with the frame, such as a length field that can specify the length of a frame 500, or the length of the data symbols 530. Further, the SIG field 520 can include fields that facilitate transmission of packets between a STA 106 and an AP 104. For example, as will be described in more detail with respect to FIGs. 6 and 7, the SIG field 520 can be used to identify an optimal modulation and coding scheme (MCS) for communication between the STA 106 and the AP 104. Table 1 depicts one example embodiment of the one or more fields that may be included in a SIG field 520.
  • MCS modulation and coding scheme
  • STA 106 determining an MCS for communicating with the AP 104 that will provide the best data rate with respect to the capabilities of the STA 106 and the AP 104 as well as the condition of the transmission medium during a given time period.
  • MCS correlates to a data rate for communication between the STA 106 and the AP 104.
  • FIG. 6 presents a flowchart for one embodiment of a data transmission process 600.
  • the process 600 can be implemented by any wireless node that can transmit and receive frames.
  • a STA 106 can implement the process 600.
  • the process 600 enables the STA 106 to determine an MCS that is currently optimal for transmitting data without performing a convergence process.
  • the amount of time required to transmit a packet is decreased. Further, in some cases, the amount of power expended to transmit the packet is also reduced.
  • the process 600 begins at block 602 when the STA 106 establishes a link with the AP 104.
  • the STA 106 identifies to the AP 104 a set of MCSes supported by the STA 106.
  • the STA 106 may identify each MCS individually that the STA 106 can support, or the STA 106 may identify the MCS associated with the fastest data rate that the STA 106 supports. In some embodiments, identifying the MCS associated with the fastest data rate that the STA 106 supports implies that the STA 106 can support any MCS associated with a slower data rate.
  • the STA 106 in some implementations, may identify the MCSes it supports during the process associated with block 602. In certain embodiments, the block 604 is optional.
  • the STA 106 sends a modulation and coding scheme request to the AP 104 using a physical layer preamble 510.
  • the modulation and coding scheme request is generally associated with a request by the STA 106 to the AP 104 to determine the MCS associated with the fastest data rate that the STA 106 can use to ensure correct decoding of data sent by the STA 106 to the AP 104 or recipient of the data.
  • the physical layer preamble 510 is sent without including any data symbols 530.
  • sending the physical layer preamble 510 without including data symbols 530 reduces the overhead and expenditure of network resources.
  • the frame comprising the physical layer preamble 510 may be transmitted faster and with the use of less power compared to a frame that includes data symbols.
  • the physical layer preamble 510 may include data symbols 530.
  • the STA 106 may include a first set of data while transmitting the modulation and coding scheme request to the AP 104.
  • the STA 106 uses the modulation and coding scheme associated with the lowest data rate that the STA 106 supports to send the modulation and coding scheme request.
  • a different modulation and coding scheme may be used.
  • sending a modulation and coding scheme request to the AP 104 can include the STA 106 configuring the SIG field 520 of the physical layer preamble 510 to create the modulation and coding scheme request.
  • Configuring the SIG field 520 can include setting the values of one or more fields that may be included as part of the SIG field 520, such as those fields listed in Table 1 .
  • Table 2 below illustrates one possible configuration for the example fields of the SIG field 520 listed in Table 1 for a modulation and coding scheme request.
  • Beacon/NDP 1 Set to 0
  • the number of possible modulation and coding schemes is less than the number of possible values that can be specified by the number of bits allocated to the MCS field of the SIG field 520.
  • the number of bits allocated to the MCS field is four allowing for a possibility of sixteen values. If for example, the nodes or devices of the wireless communication system 100 are all configured to support ten or less possible modulation and coding schemes, it is possible to associate the additional possible values for the bit field, which would be six values in this example, for other purposes. Generally, any value for the MCS field that is not associated with a valid MCS can be used for other purposes.
  • the decimal value 15, or binary value 1 1 1 1 for the MCS field can be used to indicate that the physical layer preamble 510 is being used as a modulation and coding scheme request frame. It is possible to use additional fields of the SIG field 520 to identify the purpose of the physical layer preamble 510.
  • the STA 106 can use a combination of the MCS field and the Beacon/NDP field to indicate a modulation and coding scheme request. For instance, by setting the MCS field to 1 1 1 1 and the Beacon/NDP field to 0, the STA 106 can specify that the frame it is sending at block 606 is a modulation and coding scheme request.
  • other fields of the SIG field 520 may be set to facilitate sending the modulation and coding scheme request.
  • the STA 106 can set the SSID hash field to a value or the hash of a value associated with the AP 104 including the SSID, BSID, or MAC address of the AP 104.
  • other fields of the SIG field 520 may be set differently compared to when data symbols are included with the frame 500.
  • the length field may be set to zero in both the modulation and coding scheme request as well as in a modulation and coding scheme response because, for example, no data symbols are included with the frame 500.
  • the STA 106 receives a modulation and coding scheme feedback response from the AP 104 via a frame that includes a physical layer preamble without including data symbols.
  • the STA 106 determines a modulation and coding scheme (MCS) based on the modulation and coding scheme feedback response.
  • MCS modulation and coding scheme
  • the MCS is determined based on the values of the fields included with the SIG field 520 of the modulation and coding scheme feedback response.
  • Table 2 illustrates one possible configuration for the example fields of the SIG field 520 listed in Table 1 for a modulation and coding scheme feedback response.
  • the MCS field of the SIG field 520 can be set to the MCS that the STA 106 can use to send frames to the AP 104.
  • the AP 104 specifies the MCS value of the MCS field based on a number of factors including the MCSes that the STA 106 supports, the MCSes that that AP 104 supports, and the present condition or anticipated condition of the communication medium associated with the BSA 102. In some embodiments, other factors may be used to determine the MCS, such as historical load of the AP 104.
  • the MCS identified in the MCS field of the SIG field 520 may be associated with the fastest data rate that the STA 106 can use to transmit data to ensure correct decoding by the AP 104 and/or the recipient of the data.
  • the MCS identified may be associated with the fastest data rate that the STA 106 can use during a certain time period. For example, if a large number of STAs are currently transmitting a large number of data packets across the medium, to ensure correct decoding of transmitted data, the STA 106 may need to use an MCS associated with a lower data rate compared to a time period when a smaller number of STAs are transmitting a smaller number of data packets.
  • the STA 106 can identify a number of available streams based on the modulation and coding scheme feedback response.
  • the number of streams can be determined from a Num SS field, as indicated in Table 3, set by the AP 104.
  • the number of streams refers to the streams that the AP 104 has identified as available for the STA 106.
  • the identified number of streams may be less than or equal to the total number of streams that the AP 104 may be capable of supporting. For instance, an AP 104 that can support 4 streams of traffic may specify during high periods of data traffic that one stream is available for the STA 106.
  • block 612 may be optional.
  • the STA 106 can transmit data to the AP 104, or to a data recipient, using the modulation and coding scheme identified at block 610. In some embodiments, the STA 106 may also use the number of streams identified at block 612 to facilitate transmitting data to the AP 104, or to a data recipient. At block 616, the STA 106 receives an acknowledgement packet from the AP 104 or the recipient of the data.
  • FIG. 7 presents a flowchart for one embodiment of a data reception process 700.
  • the process 700 can be implemented by any wireless node that can transmit and receive frames.
  • an AP 104 can implement the process 700.
  • the process 700 enables an AP 104 to specify to a STA 106 an MCS that is currently optimal for transmitting data without performing a convergence process.
  • the amount of time required to transmit a packet is decreased. Further, in some cases, the amount of power expended to transmit the packet is also reduced.
  • the process 700 begins at block 702 when the AP 104 establishes a link with the STA 106.
  • the AP 104 receives from the STA 106 the identity of a set of MCSes supported by the STA 106.
  • the AP 104 may receive the identity of each individual MCS supported by the STA 106.
  • the AP 104 may receive the identity of the MCS associated with the fastest data rate that the STA 106 supports.
  • identifying the MCS associated with the fastest data rate that the STA 106 supports implies that the STA 106 can support any MCS associated with a slower data rate.
  • the AP 104 in some implementations, may receive the identity of the MCSes the STA 106 supports during the process associated with block 702. In certain embodiments, the block 704 is optional.
  • the AP 104 receives a modulation and coding scheme request from the STA 106 via a physical layer preamble 510.
  • the physical layer preamble 510 received at block 706 corresponds to the physical layer preamble sent at block 606 above.
  • the physical layer preamble 510 of block 706 may include a SIG field 520 with the set of fields and values listed above in Table 2. Further, in some implementations, some or all of the embodiments described above with respect to block 606 may apply to block 706.
  • the AP 104 transmits a modulation and coding scheme feedback response to the STA 106 specifying a supported modulation and coding scheme.
  • the modulation and coding scheme feedback response can be transmitted using a physical layer preamble 510.
  • the modulation and coding scheme feedback response may include a SIG field 520 with the set of fields and values described above in Table 3. Further, in some implementations, some or all of the embodiments described above with respect to block 608 may apply to block 708.
  • the AP 104 receives data from the STA 106 using the modulation and coding scheme specified in the modulation and coding scheme feedback response.
  • the AP 104 may receive data from the STA 106 using a modulation and coding scheme associated with a slower data rate than the modulation and coding scheme that the AP 104 specified as part of the modulation and coding scheme feedback response.
  • the STA 106 may transmit data to another STA using the modulation and coding scheme specified by the AP 104 as part of the modulation and coding scheme feedback response.
  • the AP 104 transmits an acknowledgement packet or frame to the STA 106.
  • the AP 104 may use the same MCS to transmit the acknowledgement packet as the AP 104 identified in the modulation and coding scheme feedback response. In some embodiments, the AP 104 uses the same MCS to transmit the acknowledgment packet at the STA 106 used to transmit the data.
  • FIG. 8 illustrates an example of a packet flow 800 in accordance with an embodiment of the present disclosure.
  • the packet flow 800 is associated with a STA 106.
  • the flow begins at block 810 with the STA 106 sending an MCS request to an AP 104.
  • the MCS request is associated with a request for the AP 104 to specify the MCS associated with the fastest data rate that the STA 106 can use to transmit data to ensure correct decoding by the recipient of the data.
  • the AP 104 is an AP with which the STA 106 has established a link.
  • the STA 106 may broadcast the MCS request without specifying a specific recipient to receive the MCS request.
  • the STA 106 receives an MCS feedback response from the
  • the STA 106 may receive the MCS feedback response from an AP with which the STA 106 has established a link. However, in some embodiments, the STA 106 may receive the MCS feedback response from an AP with which the STA 106 has not established a link. In certain embodiments, the STA 106 may establish a link with the AP that provided the MCS feedback response. In a number of embodiments, the MCS feedback response is received within a Short Interframe Space (SIFS) 802. In certain embodiments, the MCS feedback response is broadcast without identifying a specific STA.
  • SIFS Short Interframe Space
  • the STA 106 can identify that the MCS feedback response is intended for the STA 106 based on whether the MCS feedback response was received within a SIFS 802. In some embodiments, if the MCS feedback response is not received within a SIFS 802, the STA 106 can determines that the AP 104 failed to receive the MCS request.
  • the STA 106 After receiving the MCS feedback response, the STA 106 uses the
  • the STA 106 in some embodiments, will receive an acknowledgement packet at block 840. Generally, if the transmission of data is successful, the STA 106 receives the acknowledgement packet within a SIFS 804.
  • certain embodiments of the present disclosure provide for reduced transmission time and reduced power usage compared to systems using legacy MCS request processes or that default to the MCS associated with the slowest data rate.
  • simulations of a sensor sending a 256 byte packet with a 2.5 MHz bandwidth indicate transmission time, and consequently power savings, of approximately 55% compared to using the MCS associated with the lowest data rate, and savings of approximately 30% compared to using legacy MCS request methods.
  • FIG. 9 illustrates another example of a wireless device 900 that may be employed within the wireless communication system of FIG. 1 .
  • the wireless device 900 comprises a MCS request transmitting module 902, a receiving module 904, a data transmitting module 906, and a determining module 908.
  • the MCS request transmitting module 902 is capable of transmitting an MCS request to an AP 104. Further, the MCS request transmitting module 902 may be configured to perform one or more of the functions discussed above with respect to the block 606 illustrated in FIG. 6.
  • the MCS request transmitting module 902 may correspond to one or more of the transmitter 210 and the transceiver 214. Further, the MCS request transmitting module 902 may include one or more of the processor 204, the DSP 220, the memory 206, and any other component that may facilitate performing one or more of the functions discussed above with respect to the block 606.
  • the receiving module 904 is capable of receiving a modulation and coding scheme feedback response from an AP 104. Further, the receiving module 904 may be configured to perform one or more of the functions discussed above with respect to the block 608. The receiving module 904 may correspond to one or more of the receiver 212 and the transceiver 214. Further, the receiving module 904 may include one or more of the processor 204, the DSP 220, the memory 206, the signal detector 218, and any other component that may facilitate performing one or more of the functions discussed above with respect to the block 608.
  • the data transmitting module 906 is capable of transmitting data to an AP 104 or another wireless device or STA. Further, the receiving module 904 may be configured to perform one or more of the functions discussed above with respect to the block 614.
  • the data transmitting module 906 may correspond to one or more of the transmitter 210 and the transceiver 214. Further, the data transmitting module 906 may include one or more of the processor 204, the DSP 220, the memory 206, and any other component that may facilitate performing one or more of the functions discussed above with respect to the block 614.
  • the determining module 908 is capable of determining an MCS based on a modulation and coding scheme feedback response received from an AP 104. Further, the determining module 908 may be configured to perform one or more of the functions discussed above with respect to the block 610 and/or the block 612. The determining module 908 may correspond to one or more of the processor 204 and the DSP 220. Further, the determining module 908 may include one or more of the memory 206, the signal detector 218, and any other component that may facilitate performing one or more of the functions discussed above with respect to the block 610 and/or the block 612.
  • FIG. 10 illustrates an example of an access point 1000 that may be employed within the wireless communication system of FIG. 1 .
  • the access point 1000 comprises a MCS request receiving module 1002, a data receiving module 1004, and a MCS feedback response transmitting module 1006.
  • the MCS request receiving module 1002 is capable of receiving an MCS request from a STA 106. Further, the MCS request receiving module 1002 may be configured to perform one or more of the functions discussed above with respect to the block 706 illustrated in FIG. 7.
  • the MCS request receiving module 1002 may correspond to one or more of a receiver and a transceiver. Further, the MCS request receiving module 1002 may include one or more of a processor, a DSP, memory, and any other component that may facilitate performing one or more of the functions discussed above with respect to the block 706.
  • the data receiving module 1004 is capable of receiving data from a STA 106. Further, the data receiving module 1004 may be configured to perform one or more of the functions discussed above with respect to the block 710.
  • the data receiving module 1006 may correspond to one or more of a receiver and a transceiver. Further, the data receiving module 1004 may include one or more of a processor, a DSP, memory, a signal detector, and any other component that may facilitate performing one or more of the functions discussed above with respect to the block 710.
  • the MCS feedback response transmitting module 1006 is capable of transmitting an MCS feedback response to a STA 106. Further, the MCS feedback response transmitting module 1006 may be configured to perform one or more of the functions discussed above with respect to the block 708 illustrated in FIG. 7. The MCS feedback response transmitting module 1006 may correspond to one or more of a transmitter and a transceiver. Further, the MCS feedback response transmitting module 1006 may include one or more of a processor, a DSP, a memory, and any other component that may facilitate performing one or more of the functions discussed above with respect to the block 708.
  • determining encompasses a wide variety of actions. For example, “determining” may include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure), ascertaining and the like. Also, “determining” may include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory) and the like. Also, “determining” may include resolving, selecting, choosing, establishing and the like. Further, a "channel width” as used herein may encompass or may also be referred to as a bandwidth in certain aspects.
  • a phrase referring to "at least one of a list of items refers to any combination of those items, including single members.
  • "at least one of: a, b, or c” is intended to cover: a, b, c, a-b, a-c, b-c, and a-b-c.
  • DSP digital signal processor
  • ASIC application specific integrated circuit
  • FPGA field programmable gate array signal
  • PLD programmable logic device
  • a general purpose processor may be a microprocessor, but in the alternative, the processor may be any commercially available processor, controller, microcontroller or state machine.
  • a processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.
  • the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted over as one or more instructions or code on a computer-readable medium.
  • Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another.
  • a storage media may be any available media that can be accessed by a computer.
  • such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.
  • any connection is properly termed a computer- readable medium.
  • the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave
  • the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium.
  • Disk and disc includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers.
  • computer readable medium may comprise non-transitory computer readable medium (e.g., tangible media).
  • computer readable medium may comprise transitory computer readable medium (e.g., a signal). Combinations of the above should also be included within the scope of computer-readable media.
  • the methods disclosed herein comprise one or more steps or actions for achieving the described method.
  • the method steps and/or actions may be interchanged with one another without departing from the scope of the claims.
  • the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.
  • a storage media may be any available media that can be accessed by a computer.
  • such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer.
  • Disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and Blu-ray® disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers.
  • a computer program product may comprise a computer readable medium having instructions stored (and/or encoded) thereon, the instructions being executable by one or more processors to perform the operations described herein.
  • the computer program product may include packaging material.
  • Software or instructions may also be transmitted over a transmission medium.
  • a transmission medium For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of transmission medium.
  • DSL digital subscriber line
  • modules and/or other appropriate means for performing the methods and techniques described herein can be downloaded and/or otherwise obtained by a user terminal and/or base station as applicable.
  • a user terminal and/or base station can be coupled to a server to facilitate the transfer of means for performing the methods described herein.
  • various methods described herein can be provided via storage means (e.g., RAM, ROM, a physical storage medium such as a compact disc (CD) or floppy disk, etc.), such that a user terminal and/or base station can obtain the various methods upon coupling or providing the storage means to the device.
  • storage means e.g., RAM, ROM, a physical storage medium such as a compact disc (CD) or floppy disk, etc.
  • CD compact disc
  • floppy disk etc.
  • any other suitable technique for providing the methods and techniques described herein to a device can be utilized.

Landscapes

  • Engineering & Computer Science (AREA)
  • Quality & Reliability (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Dans l'un de ses modes de réalisation, la présente invention se rapporte à un procédé de communication sans fil. Le procédé selon l'invention consiste à transmettre une requête de schéma de modulation et de codage à un point d'accès. La requête de schéma de modulation et de codage est transmise au moyen d'une première trame de préambule de couche physique. La requête de schéma de modulation et de codage comprend un identifiant associé au point d'accès. Le procédé consiste d'autre part à recevoir, du point d'accès, à une station, une réponse en retour de schéma de modulation et de codage en réponse à la transmission de la requête de schéma de modulation et de codage. La réponse en retour de schéma de modulation et de codage est reçue au moyen d'une seconde trame de préambule de couche physique. Le procédé selon l'invention consiste par ailleurs à déterminer un schéma de modulation et de codage sur la base de la réponse en retour de schéma de modulation et de codage. Le procédé selon l'invention consiste enfin à transmettre des données au point d'accès au moyen du schéma de modulation et de codage identifié.
PCT/US2012/053088 2011-09-02 2012-08-30 Systèmes et procédés pour optimiser des débits de transmission de données sans fil WO2013033361A1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
US201161530745P 2011-09-02 2011-09-02
US61/530,745 2011-09-02
US13/595,475 2012-08-27
US13/595,475 US20130223422A1 (en) 2011-09-02 2012-08-27 Systems and methods for optimizing wireless transmission data rates

Publications (1)

Publication Number Publication Date
WO2013033361A1 true WO2013033361A1 (fr) 2013-03-07

Family

ID=46846014

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2012/053088 WO2013033361A1 (fr) 2011-09-02 2012-08-30 Systèmes et procédés pour optimiser des débits de transmission de données sans fil

Country Status (2)

Country Link
US (1) US20130223422A1 (fr)
WO (1) WO2013033361A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014182836A1 (fr) 2013-05-07 2014-11-13 Huawei Technologies, Co., Ltd. Système et procédé d'indication d'un identifiant de réseau sans fil
CN108141310A (zh) * 2015-07-17 2018-06-08 无线电广播技术研究所有限公司 用于发射数据传输信号的发射器和用于接收该数据传输信号的接收器，该发射器和接收器中每个都可以取决于附加的信息信号而在编码方案和/或调制方案之间切换

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9635601B2 (en) * 2012-03-09 2017-04-25 Huawei Technologies Co., Ltd. 802.11 PHY hashed SSID
WO2016086422A1 (fr) 2014-12-05 2016-06-09 华为技术有限公司 Procédé de configuration à plusieurs émetteurs-récepteurs, procédé de réutilisation des canaux de plusieurs émetteurs-récepteurs et appareils
US20170026976A1 (en) * 2015-07-20 2017-01-26 Qualcomm Incorporated Flexible coding schemes
US10924379B1 (en) * 2019-07-23 2021-02-16 Rohde & Schwarz Gmbh & Co. Kg Method and device for controlling transmission rate of a device under test
US11923977B1 (en) * 2022-08-26 2024-03-05 Qualcomm Incorporated Decoder success predictor signaling for adjusting MIRS scheduling policy

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060248429A1 (en) * 2005-04-04 2006-11-02 Interdigital Technology Corporation Method and system for improving responsiveness in exchanging frames in a wireless local area network
US20070171933A1 (en) * 2006-01-23 2007-07-26 Interdigital Technology Corporation Medium access control and physical layer headers for high throughput data in wlan systems
US20080299962A1 (en) * 2007-05-30 2008-12-04 Assaf Kasher Providing extended range modes as part of the 802.11n standard
US20100091675A1 (en) * 2008-10-10 2010-04-15 Sony Corporation Wireless communication system, wireless communication device and wireless communication method, and computer program
WO2010150950A1 (fr) * 2009-06-23 2010-12-29 Lg Electronics Inc. Procédé d'exécution d'un procédé d'adaptation de liaison
US7965619B2 (en) * 2006-07-07 2011-06-21 Mitsubishi Electric Corporation Wireless communication system and communication control method

Family Cites Families (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7577438B2 (en) * 2005-04-25 2009-08-18 Interdigital Technology Corporation Method and system for efficient addressing and power savings in wireless systems
JP4843046B2 (ja) * 2005-11-07 2011-12-21 テレフオンアクチーボラゲット エル エム エリクソン（パブル） リンクアダプテーションのための暗黙的なシグナリング
US8787841B2 (en) * 2006-06-27 2014-07-22 Qualcomm Incorporated Method and system for providing beamforming feedback in wireless communication systems
US8363627B2 (en) * 2007-06-19 2013-01-29 Intel Corporation Modulation coding schemes for control frame transmission under 802.11N
US8948102B2 (en) * 2009-02-18 2015-02-03 Lg Electronics Inc. Channel access method for very high throughput (VHT) wireless local access network system
WO2011065750A2 (fr) * 2009-11-24 2011-06-03 한국전자통신연구원 Procédé de transmission d'une trame de demande de réponse et trame de réponse dans un système de communication sans fil sur une base multi-utilisateurs
WO2012030585A2 (fr) * 2010-09-01 2012-03-08 Marvell World Trade Ltd. Adaptation des liaisons dans un réseau de communication
US9806848B2 (en) * 2010-09-29 2017-10-31 Qualcomm Incorporated Systems, methods and apparatus for determining control field and modulation coding scheme information
JP5690850B2 (ja) * 2010-11-26 2015-03-25 エルジー エレクトロニクス インコーポレイティド 無線ｌａｎシステムではリンク適応に基づいて、チャネル情報を報告する方法とそれをサポートするデバイス
WO2012125511A2 (fr) * 2011-03-11 2012-09-20 Mediatek Singapore Pte. Ltd. Adaptation rapide de la liaison et commande de la puissance d'émission dans des réseaux sans fil
EP2719219B1 (fr) * 2011-06-08 2016-12-07 Marvell World Trade Ltd. Émission efficace pour réseau local sans fil à faible débit de données

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20060248429A1 (en) * 2005-04-04 2006-11-02 Interdigital Technology Corporation Method and system for improving responsiveness in exchanging frames in a wireless local area network
US20070171933A1 (en) * 2006-01-23 2007-07-26 Interdigital Technology Corporation Medium access control and physical layer headers for high throughput data in wlan systems
US7965619B2 (en) * 2006-07-07 2011-06-21 Mitsubishi Electric Corporation Wireless communication system and communication control method
US20080299962A1 (en) * 2007-05-30 2008-12-04 Assaf Kasher Providing extended range modes as part of the 802.11n standard
US20100091675A1 (en) * 2008-10-10 2010-04-15 Sony Corporation Wireless communication system, wireless communication device and wireless communication method, and computer program
WO2010150950A1 (fr) * 2009-06-23 2010-12-29 Lg Electronics Inc. Procédé d'exécution d'un procédé d'adaptation de liaison

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014182836A1 (fr) 2013-05-07 2014-11-13 Huawei Technologies, Co., Ltd. Système et procédé d'indication d'un identifiant de réseau sans fil
CN105379190A (zh) * 2013-05-07 2016-03-02 华为技术有限公司 用于指示服务集标识符的系统和方法
EP2979401A4 (fr) * 2013-05-07 2016-03-30 Huawei Tech Co Ltd Système et procédé d'indication d'un identifiant de réseau sans fil
CN105379190B (zh) * 2013-05-07 2019-07-09 华为技术有限公司 用于指示服务集标识符的系统和方法
CN108141310A (zh) * 2015-07-17 2018-06-08 无线电广播技术研究所有限公司 用于发射数据传输信号的发射器和用于接收该数据传输信号的接收器，该发射器和接收器中每个都可以取决于附加的信息信号而在编码方案和/或调制方案之间切换
CN108141310B (zh) * 2015-07-17 2021-03-26 无线电广播技术研究所有限公司 用于发射信号的发射器和用于接收该信号的接收器

Also Published As

Publication number Publication date
US20130223422A1 (en) 2013-08-29

Similar Documents

Publication Publication Date Title
EP2932767B1 (fr) Système et procédé permettant d'améliorer la communication sur un réseau sans fil
EP2944149B1 (fr) Procédé, appareil et programme informatique pour la sélection de paramètres d'accès au support pour chaque session de communication
US9226241B2 (en) Systems and methods for low power medium access
US20130223422A1 (en) Systems and methods for optimizing wireless transmission data rates
US9351184B2 (en) System and method for tuning medium access parameters
US9485658B2 (en) System and method for improved communication on a wireless network
US9693300B2 (en) System and method for saving power using restricted access windows
US9320020B2 (en) Systems and methods for partial aid selection
US9048936B2 (en) Systems and methods for managing on-time of wireless receivers
US20150124678A1 (en) System and method for access point power management signalling in a wireless network
AU2015335615A1 (en) Uneven bit distributions for encoder parsing
US9191882B2 (en) Systems and methods for improved association in wireless networks

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12758953

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 12758953

Country of ref document: EP

Kind code of ref document: A1